Severe climate-induced water shortage and extremes in Crete

Abstract

Climate change is expected to have a significant impact on the hydrologic cycle, creating changes in freshwater resources. The Intergovernmental Panel on Climate Change (IPCC) predicts that, as a result, floods and prolonged droughts will take place at increasingly frequent periods. The Mediterranean has been described as one of the main climate change "hot-spots", with recent simulations showing a collective picture of substantial drying and warming. This effect appears more pronounced during warm periods, when the seasonal decrease of precipitation can exceed control climatology by 25-30%. Despite the decreasing annual rainfall trend, an increase in the amount and intensity of wintertime rainfall is evident. However, the scientific question on the quantitative impact of these signals to small scale coastal watersheds and Mediterranean islands has not been answered. The state-of-the-art Ensembles dataset was employed to assess the impact of the changing climate on the water availability of the island of Crete at basin scale. Here, the Ensembles precipitation and temperature data is used as input for a rainfall-runoff model previous calibrated for the whole island with the principle of regionalization. Data analysis for the period Ioannis K. Tsanis on leave from Department of Civil Engineer, McMaster University, Canada. Electronic supplementary materialThe online version of this article (

Spatial Downscaling of Alien Species Presences Using Machine Learning

“…Crete receives on average about 7.7 billion m 3 of rainfall, of which only and 10-15% produces runoff, while 68-76% evapotranspires and 14-17% infiltrates (Koutroulis et al, 2016). The intense tectonic history has formed the island's complex topography that ranges from sea level to 2,450 m, and is abundant in small, ephemeral watersheds (Tsanis et al, 2011). This highlyrugged terrain has been definitive for human development as well as its spatial allocation (Koutroulis et al, 2016).…”

Exploring the ability of current climate information to facilitate local climate services for the water sector

“…By the 2050s, this stress could increase over the whole Mediterranean basin, notably because of a 30-50 % decline in freshwater resources as a result of climate change (Milano et al 2013). Models foresee a robust largescale change of the surface water balance and the partitioning of precipitation between evapotranspiration, runoff, and groundwater flow (Schewe et al 2014;García-Ruiz et al 2011;Arnell et al 2011;Tsanis et al 2011). At the same time increasing climate change induced temperatures will most likely increase the need for irrigation in agriculture.…”

Determining the causes for the dramatic recent fall of Lake Prespa (southwest Balkans)

“…Regional precipitation and runoff are projected to decrease by up to 30% by 2100 (Milly et al 2005, Tsanis et al 2011. The NAO may be predominantly "locked" in the positive phase over the coming century, implying less winter precipitation and snow accumulation, and therefore less runoff (López-Moreno et al 2011).…”

“…The Mediterranean stands out globally due to its sensitivity to climate change and human pressure on the available water resources (Alvarez-Cobelas et al 2005, Matzinger et al 2006a, Giorgi and Lionello 2008, Somot et al 2008, Tsanis et al 2011, Lelieveld et al 2012. Drought frequency and duration have increased in many of its regions over recent decades, while winter-spring ("wet-season") precipitation has decreased in all mountain chains bordering the Mediterranean from northwest to northeast (e.g.…”

“…Coops et al 2003, AlvarezCobelas et al 2005, Crisman et al 2005. Future climate scenarios predict an increase in the frequency/ intensity of regional droughts, declining wet-season precipitation and runoff decreases across the northern Mediterranean region; the exploitation of freshwater resources is expected to increase significantly due to anticipated climatic and socio-economic changes (Alvarez-Cobelas et al 2005, Milly et al 2005, Giannakopoulos et al 2009, Tsanis et al 2011, Lelieveld et al 2012. In the light of these ongoing and projected threats, it is extremely important to protect the remaining lake-wetland systems in order to maintain global biodiversity and ensure sustainable regional water availability.…”